1. Field of the Invention
The present invention relates to a coupler for a flexible corrugated pipe having corrugations formed along the outer peripheral surface thereof, and more particularly, to a coupler for a corrugated pipe that is capable of being easily coupled to the corrugated pipe just by fitting the corrugated pipe thereinto and fastening a cap nut to a fastening member.
2. Background of the Related Art
One of conventional couplers for a corrugated pipe is disclosed in U.S. Pat. No. 7,980,601, which is issued to the same applicant as the present invention. According to the conventional coupler, in the state where a cap nut is screw-coupled to a fastening member, the corrugated pipe is pushed through the hole of the cap nut, and next, the cap nut is fastened, so that the corrugations of the corrugated pipe are compressed by means of a compressing member, and thus, the compressing member is moved to a valley portion of the corrugated pipe, thereby finishing inserting the corrugated pipe into the coupler.
When the cap nut is fastened, by the way, the end portion of the corrugated pipe is compressed in the state of being brought into contact with the fastening member, which causes the fastening member to be damaged and accordingly has a bad influence on the sealing state of the corrugated pipe.
Further, in case where the conventional coupler for the corrugated pipe is provided with a composite member having a braided net (steel net) buried into a coated material, as coating means for protecting the corrugated pipe, the lightning transmitted via the braided net of the composite member is not grounded to the outside, which causes the corrugated pipe to be damaged.